Air or gas compressor



June 8, 1943. E. c. MILLS AIR OR GAS COMPRESSOR Filed Dec. 50, 1941 4 Sheets-Sheet 1 June 8, 1943. E. c. MILLS AIR OR GAS COMPRESSOR Filed Dec. 30, 1941 4 Sheets-Sheet 2 /m ew/i/ I M M m 4 Sheets-Sheet 5 Filed Dec. 30, 1941 June 8, 1943. E. c. MILLS AIR OR GAS COMPRESSDR Filed Dec. 30, 1941 4 Sheets-Sheet 4 I P I UNITED STATES PATENT OFFICE AIR R GAS- COMPRESSOR Edward Cecil Mills, Camborne, England Application December 30, 1941, Serial No. 424,910

In Great Britain December 23, 1940 8 Claims. (01. 123-119) This invention relates to air or gas compressors driven by internal combustion engines.

One object of the invention is the provision, in a simple way, for eflicient cooling of the layout.

Another object is the provision of a simple way of means for supercharging the engine and/or the compressor.

Other objects and advantages will appear hereinafter.

According to the invention the cylinders of the engin and compressor are cooled by a current of cooling fluid produced by a fan or other pump driven by the engine, the current of fluid being led through ducting by which the correct proportions are supplied to the respective cylinders.

The invention further resides in the arrange-' ment that air for supercharging the engine or the compressor is supplied by a fan (which may be the same fan as the above) driven by the engine.

In order that the invention may be more clearly understood a portable layout of a compressor driven by an internal combustion engine in accordance with the invention will now be described, reference being made to the accompanying drawings,wherein Figure 1 is a side elevation of said layout.

Figure 2 is an end view of the same looking from the right of Figure 1.

Figure 3 is a plan of the same.

Figure 4 is a section on the line IV-IV of Figure 3.

Figure 5 is a section on the line VV of Figure 1.

Figure 6 is a section on the line VIVI of Figure 3.

Figure 'I is a side elevation sectioned in such a way as to show the flow of air to supercharge the engine and compressor cylinders.

Figure 8 is a side elevation sectioned in such a way as to show the passage of air from the low pressure to the high pressure stage of the compressor through the intercooler.

Referring to these drawings, the portable layout is the same as that described and illustrated in my co-pending application Serial No. 424,909, filed December 30, 1941 (corresponding to British patent application No. 18,034/40) and comprises an air or gas compressor having a vertical cylinder l and an internal combustion engine having vertical cylinders 2 and 3 for driving said compressor. The compressor and motor have a common crank shaft indicated at 4a, or the two crank shafts are coaxial and directly coupled together.

The compressor is of the single cylinder two stage, double acting type, and an intercooler 4 is provided, the air after the first stage of compression flowing as best shown Figure 8, from theupper' end of the cylinder I way of a conduit 5 to the upper end or the lntercooler 4 and from the lower end of said intercooler by way of a conduit 6 to the lower end of said cylinder I for the second stage of compression. Said intercooler is arranged as shown alongside the cylinders 2 and 3 of the engine. An aitercooler l is also provided, the air, after the second stage of compression, passing as best shown in Figure 4, from the lower end of the cylinder i, by way of a conduit 8, to the lower end of the half of the aitercooler tubes nearest the cylinder, and from the upper end of the said half of the aftercooler tubes by way of a conduit 9 to the upper end of the other half of the after-cooler tubes, and from the lower end or the said other half of the aftercooler tubes, by way of a conduit 9a to the point of use. Said aitercooler is arranged as shown in Figure 3 at the side of the cylinders remote from the intercooler, and at a position about between v the cylinders l and 3.

direction into theian casing H as indicated bythe plain arrows in Figures 1, 3 and 7. From the left-hand side of the fan casing II (as seen in Figure 2) duct for cooling air extends first upwards at it, then turns longitudinally horizontally at l3 (Figures 1, 3, 7 and 8), then turns horizontally inwardly at l4 (Figures 2, 3, 4 and 6), embracing within itself the intercooler 4 as shown and continues inwardly embracing within itself the cylinders 2 and 3. These cylinders are provided with vanes i5. Thus the cooling air flowing along this duct cools the intereooler 4 and the cylinders 2 and 3. a

This duct is built up of plating and is generally of rectangular cross-section as shown. The roof of said duct is seen to terminate at l6 (Figures 3 and 6) short or the axes of the cylinders 2 and 3. The floor of'the duct is constituted by the top of the crank case. Theright-hand wall of said duct (as seen in Figure 3) terminates at the point I! beyond the axes of said cylinders. The other wall l8 (Figures 3 and 4) proceeds beyond said cylinders for a purpose which will hereinafter appear.

This wall I8, which passes between the cylinders I and 3 is louvred as indicated at 18a, at the region beyond the intercooler I to enable the correct proportion of cooling air to flow through, as indicated by the plain arrows in Figure 3, for the purpose of cooling the cylinder l and aftercooler 7. This cooling air leaving the louvres is guided by further ducts to flow round the cylinder I and its vanes l9, as shown in Figures 3 and 4, said further ducts consisting of side plates 20 and a top plate terminating at 2| (Figure 3), the bottom of the duct being constituted by the top of the crank case. A branch of the same cooling air in the correct proportion is guided to flow over the aftercooler by means of further ducts consisting of side plates constituted respectively by the extension of the aforesaid plate l8 and by a plate 22 (Figures 3 and 4) and corresponding top and bottom plates.

It will be noted that the conduits 5 and 6 extending between the cylinder 3 and the intercooler 4 run close to the ducts guiding the cooling air to the intercooler, which arrangement further increases the cooling effect.

The system is also provided with an oil cooler 23 in the form of a vaned sump, and additional ducting 24 (Figures 1 and 5) extends from the fan casing H to and around this vaned sump, guiding the air over the vanes thereof.

Some of the air from the cooling fan III is also used to supercharge both the engine and the compressor To this end a conduit 25 branches, at the region l3, as best seen in Figure 7 from the top of the duct leading from the fan casing to the intercooler 4, and leads to the inlet 26 of the compressor cylinder I; and, from this conduit 25, branches a conduit 21, which forks and leads to the inlets 28 and 29 of the cylinders 3 and 2 as indicated.

Although the air pressure at the fan discharge will be but a few inches of water, it will supercharge slightly both the engine and the compressor and also ensure a supply of the coolest available air.

Structural details are deemed suflicientlyclear from the drawings.

It will be appreciated that the cooling system described provides. efiicient cooling with simplicity of design, permitting complete elimination of the usual radiation and water cooling system.

What I claim and desire to secure by Letters Patent is:

1. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shaft, an air duct embracing said combustiton engine cylinders for cooling same, a fan carried by said crank shaft for circulating cooling air above atmospheric pressure through said duct, louvres in said duct adjacent said compressor cylinder for directing air upon said compressor cylinder to cool same, and branch conduits leading from said air duct to the inlets of said combustion engine cylinders and said compressor cylinder for supercharging same.

' 2'. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shaft, an air duct embracing said combustion engine cylinders for cooling same, a fan carried by said crank shaft for circulating cooling airabove compressor cylinder for supercharging same with cool air.

3. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a two stage compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shaft, an intercooler connected between the two stages of said compressor cylinder means including an air duct embracing said combustion engine cylinders and said intercooler for cooling same, and branch conduits leading from said air duct to the inlets of said combustion engine cylinders and said compressor cylinder for supercharging same.

4. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, 3, two stage compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shaft, an intercooler connected between the two stages of said compressor cylinder, an aftercooler connected to the second stage of said compressor cylinder, means including an air duct embracing said combustion engine cylinders and said intercooler for cooling same, and means associated with said duct for directing a portion of the air therein upon said compressor cylinder and said aftercooler for cooling same.

5. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a two stage compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shaft, an intercooler connected between the two stages of said compressor cylinder, an aftercooler connected to the second stage of said compressor cylinder, means includin an air duct embracing said combustion engine cylinders and said intercooler for cooling same, means associated with said duct for directing a portion of the air therein upon said compressor cylinder and said aftercooler for cooling same, and branch conduits leading from said air duct to the inlets of said combustion engine cylinders and said compressor cylinder for supercharging same.

6. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a two stage compressor cylinder and a plurality of combustion engine cyl-* inders, pistons in said cylinders connected to said crank shaft, an intercooler connected between the two stages of said compressor, an aftercooler connected to the second stage of said compressor cylinder, an air duct embracin said combustion engine cylinders and said intercooler for cooling same, a fan carried by said crank shaft for circu-, lating cooling air above atmospheric pressure through said duct, louvres in said duct adjacent? said compressor cylinder and said aftercooler for directing air thereover to cool same, and branch conduits leading from a region of said air duct in advance of said combustion engine cylinders and connected to the inlets of said combustion engine cylinders and said compressor cylinder for supercharging same with cool air.

'7. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shalt, an oil sump beneath said crank shaft, means including an air duct embracing said combustion engine cylinders for cooling same, means associated with said duct for directing a portion of the air therein upon said compressor cylinder for cooling same, branch conduits leading from said air duct to the inlets of said combustion engine cylinders and said compressor cylinder for supercharging same, and a branch conduit leading irom. said air duct to said oil sump for cooling same.

8. A gas or air compressor driven by an internal combustion engine, comprising, in combination with a crank shaft, a two stage compressor cylinder and a plurality of combustion engine cylinders, pistons in said cylinders connected to said crank shaft, an intercooler connected between the two stages of said compressor cylinder, and means including an air duct embracing said combustion engine cylinders and said intercooler for cooling same.

EDWARD CECIL MILLS. 

